Saliva and Sweat: The Utility of Oral Fluid Testing in Impaired Driving and Workplace Forensics

Traditional forensic toxicology has long relied on blood and urine specimens for establishing drug consumption, intoxication, or impairment. However, biological matrices such as oral fluid (saliva) and transdermal sweat have fundamentally transformed modern forensic applications, particularly in Driving Under the Influence of Drugs (DUID) and workplace compliance monitoring. Offering non-invasive collection, real-time correlation with recent drug intake, and resistance to traditional adulteration techniques, these alternative matrices provide distinct advantages. This review explores the physiological mechanisms of drug excretion into oral fluid and sweat, analytical screening and confirmation methodologies (such as LC-MS/MS and Point-of-collection testing devices), and their expanding regulatory frameworks in global transport safety and occupational testing.